获得屏幕相关的辅助类

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Rect;
import android.util.DisplayMetrics;
import android.view.View;
import android.view.WindowManager;

/**
 * 获得屏幕相关的辅助类
 */
public class ScreenUtils
{
   private ScreenUtils()
   {
      /* cannot be instantiated */
      throw new UnsupportedOperationException("cannot be instantiated");
   }

   /**
    * 获得屏幕高度
    * @param context
    * @return
    */
   public static int getScreenWidth(Context context)
   {
      WindowManager wm = (WindowManager) context
            .getSystemService(Context.WINDOW_SERVICE);
      DisplayMetrics outMetrics = new DisplayMetrics();
      wm.getDefaultDisplay().getMetrics(outMetrics);
      return outMetrics.widthPixels;
   }

   /**
    * 获得屏幕宽度 
    * @param context
    * @return
    */
   public static int getScreenHeight(Context context)
   {
      WindowManager wm = (WindowManager) context
            .getSystemService(Context.WINDOW_SERVICE);
      DisplayMetrics outMetrics = new DisplayMetrics();
      wm.getDefaultDisplay().getMetrics(outMetrics);
      return outMetrics.heightPixels;
   }

   /**
    * 获得状态栏的高度 
    * @param context
    * @return
    */
   public static int getStatusHeight(Context context)
   {
      int statusHeight = -1;
      try
      {
         Class<?> clazz = Class.forName("com.android.internal.R$dimen");
         Object object = clazz.newInstance();
         int height = Integer.parseInt(clazz.getField("status_bar_height")
               .get(object).toString());
         statusHeight = context.getResources().getDimensionPixelSize(height);
      } catch (Exception e)
      {
         e.printStackTrace();
      }
      return statusHeight;
   }

   /**
    * 获取当前屏幕截图，包含状态栏 
    * @param activity
    * @return
    */
   public static Bitmap snapShotWithStatusBar(Activity activity)
   {
      View view = activity.getWindow().getDecorView();
      view.setDrawingCacheEnabled(true);
      view.buildDrawingCache();
      Bitmap bmp = view.getDrawingCache();
      int width = getScreenWidth(activity);
      int height = getScreenHeight(activity);
      Bitmap bp = null;
      bp = Bitmap.createBitmap(bmp, 0, 0, width, height);
      view.destroyDrawingCache();
      return bp;

   }

   /**
    * 获取当前屏幕截图，不包含状态栏
    * @param activity
    * @return
    */
   public static Bitmap snapShotWithoutStatusBar(Activity activity)
   {
      View view = activity.getWindow().getDecorView();
      view.setDrawingCacheEnabled(true);
      view.buildDrawingCache();
      Bitmap bmp = view.getDrawingCache();
      Rect frame = new Rect();
      activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame);
      int statusBarHeight = frame.top;

      int width = getScreenWidth(activity);
      int height = getScreenHeight(activity);
      Bitmap bp = null;
      bp = Bitmap.createBitmap(bmp, 0, statusBarHeight, width, height
            - statusBarHeight);
      view.destroyDrawingCache();
      return bp;
   }
}